About this replacement
Dell Latitude CS / CSX — 11.1V Li-ion Replacement Battery (7012P / 8012P)
This is an 11.1V, 3600mAh (39.96Wh) Li-ion replacement battery for the Dell Latitude CS and Latitude CSX notebooks. It replaces OEM part numbers 7012P, 8012P, BAT-LCS, IM-M150260, and IM-M150260-GB. Install it when the original cell no longer holds a charge or the system refuses to run on battery at all.
- Latitude CS and CSX compatibility: Both the CS and CSX share the same battery bay geometry, connector pinout, and 11.1V nominal rail. The BMS in this pack communicates over the same SMBus protocol the original Dell controller expects, so the system registers it without driver changes.
- Bench tested on actual hardware: We cycled this pack through charge and full-load discharge on a Latitude CS unit. The BMS held cutoff voltage correctly at the low end and accepted a full charge without tripping the overcurrent protection on the host controller.
- Post-install discharge cycle on the Latitude CS: After fitting this battery, run one full discharge to hibernate cutoff, then charge uninterrupted to 100%. This forces the BIOS battery learn cycle to reset against the new cell data and clears the inaccurate health warning that appears after every cell swap on this platform.
BIOS reporting battery health as poor after replacing the cell on the Latitude CS
The Latitude CS BIOS reads health data from EEPROM embedded in the battery pack, not from live cell measurements. When a new cell goes in, that EEPROM data does not match the history the BIOS expects, so it flags the battery as degraded immediately. This is a firmware-side artefact, not a fault with the replacement cell. Running one complete discharge-to-hibernate followed by an uninterrupted full charge resets the learn cycle and clears the warning.
Latitude CS shutting down at 20–30% remaining shown on screen
This happens when the fuel gauge IC has not yet calibrated against the new cell's actual charge curve. The percentage shown is based on stale data from the previous degraded cell, so the BIOS cuts power when the real cell voltage drops below the safety threshold — even though the gauge still reads 20–30%. Run two full discharge-to-hibernate and full-recharge cycles without interruption. After the second cycle, the fuel gauge IC recalibrates and the displayed percentage will track actual remaining capacity accurately.